Ingredient guide
L-tyrosine is an amino acid used to make dopamine and norepinephrine. Trials support its use for cognitive performance during acute stress, such as cold, sleep deprivation, or military stress, at doses of 100 to 150 mg per kg of body weight.
Moderate evidenceL-tyrosine is a non-essential amino acid the body makes from phenylalanine. It is the precursor for the catecholamine neurotransmitters dopamine and norepinephrine, plus the thyroid hormones. Acute stress depletes these neurotransmitters, which is the rationale for using tyrosine before demanding tasks.
A 2015 rapid evidence assessment made a weak recommendation in favour of tyrosine for cognitive stress, with all studies showing a positive effect. A trial in military cadets showed that tyrosine improved cognitive performance and reduced blood pressure after one week of combat training. Studies using 150 mg/kg L-tyrosine before testing in cold conditions reduced response time and improved accuracy. We grade the evidence as moderate for acute cognitive stress use.
Acute stress trials use 100 mg to 150 mg per kg of body weight, taken 60 minutes before the stressor. For a 70 kg adult that is about 7 g to 10 g. Take on an empty stomach. Ask your healthcare provider before use if you take thyroid medicine or MAO inhibitors.
Yes, for acute cognitive stress like cold, sleep deprivation, or military training. Studies use 100 to 150 mg per kg of body weight before the stressor.
Short-term use (up to 3 months) at typical study doses is well tolerated. Long-term high-dose safety is not well studied.
